Valve controllers or other process control devices may be operated in environments that are susceptible to explosions or fires. For example, valve controllers may control valves that control oil flow in a refinery or the flow of chemicals in a chemical plant or manufacturing facility. The valve controllers typically include modules having an enclosure or housing that may accumulate fluids and/or gases from the potentially combustible environments. Sparks or overheating by electronics, wiring, or motors within the modules may ignite a fluid inside the module and initiate a flame, a fire, or an explosion. The enclosure or housing may contain the flame, fire, or explosion to within the module. However, the enclosure or housing may include passages or channels that enable a fluid to flow between the outside of the enclosure or housing and the inside of the enclosure or housing to enable electronics of the module to measure properties of the fluid.
Typically, a flame arrestor situated within a channel or passage of the module permits the flow of the fluid through the passage but prevents a flame, a fire, or an explosion from crossing the passage into a potentially combustible environment outside the module. A flame arrestor prevents (e.g., extinguishes) a flame or an explosion from reaching the outside environment by absorbing heat associated with the flame or explosion. Thus, the flame arrestor enables a fluid to enter the module from the outside environment while preventing a fire or explosion from exiting a housing or enclosure of the module and igniting the outside environment.